wallet: fix minor locking thing in set_reserved_state_of_address
wallet: fix minor locking thing in set_reserved_state_of_address

follow-up 6040e953a32803a65a10f62d4f7ac815d1a9e590

spesmilo/electrum,pooler/electrum-ltc,spesmilo/electrum,spesmilo/electrum,wakiyamap/electrum-mona,pooler/electrum-ltc,spesmilo/electrum,pooler/electrum-ltc,pooler/electrum-ltc,wakiyamap/electrum-mona,wakiyamap/electrum-mona,wakiyamap/electrum-mona